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51.
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Wall-eyed bilateral internuclear ophthalmoplegia (WEBINO) is a rarely reported syndrome. There is dispute about whether WEBINO is caused by a pontine or a midbrain lesion and whether the medial rectus subnuclei are implicated. In a study of the clinical and imaging features of four patients with WEBINO, we found that that three of four lesions involved the midbrain but not necessarily the medial rectus subnuclei. 相似文献
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Pilar Nicolás 《Hereditary cancer in clinical practice》2007,5(3):144-152
The specific characteristics of genetic data lead to ethical-legal conflicts in the framework of genetic diagnosis. Several international organisations, including UNESCO and the Council of Europe, have enacted rules referring to the use of genetic information. This paper discusses possible legal and ethical criteria that could be used in genetic testing. 相似文献
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通过深入分析我国中医药科学性研究中所存在的问题,依据协同学理论,提出了中医药科学性的理论基础是协同学的观点。基于此,阐释了中医药科学性的协同学解释,这在一定意义上为中医药科学性的研究提供了新的视角和有益的启示。 相似文献
57.
Wen-Ni Chang Jen-Ning Tsai Bing-Hung Chen Huei-Sheng Huang Tzu-Fun Fu 《Drug metabolism and disposition》2007,35(11):2127-2137
Serine hydroxymethyltransferase (SHMT) provides activated one-carbon units required for the biosynthesis of nucleotides, protein, and methyl group by converting serine and tetrahydrofolate to glycine and N(5),N(10)-methylenetetrahydrofolate. It is postulated that SHMT activity is associated with the development of methotrexate resistance and the in vivo activity of SHMT is regulated by the binding of N(5)-CHO-THF, the rescue agent in high-dose methotrexate chemotherapy. The aim of this study is to advance our understanding of the folate-mediated one-carbon metabolism in zebrafish by characterizing zebrafish mitochondrial SHMT. The cDNA encoding zebrafish mitochondrial SHMT was cloned, overexpressed in Escherichia coli, and purified with a three-step purification protocol. Similarities in structural, physical, and kinetic properties were revealed between the recombinant zebrafish mitochondrial SHMT and its mammalian orthologs. Surprisingly, leucovorin significantly inhibits the aldol cleavage of serine catalyzed by zebrafish cytosolic SHMT but inhibits to a lesser extent the reaction catalyzed by the mitochondrial isozyme. This is, to our knowledge, the first report on zebrafish mitochondrial folate enzyme as well as the differential inhibition of leucovorin on these two SHMT isoforms. Western blot analysis revealed tissue-specific distribution with the highest enrichment present in liver for both cytosolic and mitochondrial SHMTs. Intracellular localization was confirmed by confocal microscopy for both mitochondrial and cytosolic SHMTs. Unexpectedly, the cytosolic isoform was observed in both nucleus and cytosol. Together with the previous report on zebrafish cytosolic SHMT, we suggest that zSHMTs can be used in in vitro assays for folate-related investigation and antifolate drug discovery. 相似文献
58.
腰椎节段形态对峡部、小关节应力及小关节接触力影响的有限元分析 总被引:1,自引:0,他引:1
目的:探讨腰椎形态结构变化对峡部裂性滑脱及小关节退变的作用和意义。方法:采用改良的“非种子区域分割方法”及非平行“最佳切割平面”等一系列新型计算机辅助设计(CAD)方法精确建立包括椎间盘高度、腰椎小关节角、椎间盘前凸角改变的L4~L5活动节段有限元模型;在2700N轴向压缩载荷条件下,分别对各有限元模型的峡部、小关节应力、小关节接触力以及椎间盘负载进行测试。结果:压缩载荷下,腰椎活动节段峡部、小关节等效应力及小关节接触力随椎间盘高度的减小而减小,随小关节角的增大而增加,随椎间盘前凸角的增加而减小。结论:椎间盘高度、腰椎小关节角、椎间盘前凸角等形态结构变化对腰椎节段有限元模型的峡部、小关节应力及小关节接触力有明显的影响。提示腰椎峡部应力性骨折及小关节退变的发生与椎间盘高度、腰椎小关节角、椎间盘前凸角等解剖形态因素有关。 相似文献
59.
60.
Lin Bo Wang Jian Guo Shen Li Feng Dong Chao Yang Xu Wen Jun Chen Shu Duo Xie Xiang Yang Song Ning Dai Xiao Ming Yuan 《Journal of gastrointestinal surgery》2008,12(8):1359-1363
We previously reported that lymphatic mapping using isosulfan blue can be used to identify sentinel nodes (SNs). This study
was undertaken to evaluate the feasibility of using the SN technique in treating early gastric cancer and to explore its usefulness
for minimal invasive surgery. Twenty-three patients with early gastric cancer who underwent SN biopsy were retrospectively
evaluated. Based on SN evaluation, individualized surgery was performed in five patients with T1N0M0 gastric cancer. When
pathological examination of frozen sections revealed metastasis in SNs, we performed a standard D2 gastrectomy. Laparoscopic
local resection was applied when the SN biopsy was negative. Our results showed that the success rate with SN biopsy in early
gastric cancer was 100%, as were the accuracy, sensitivity, and specificity. All five patients with early gastric cancer had
SNs negative for metastases both by frozen section and by postoperative pathology. Thus, all these patients underwent laparoscopic
local resection without extended lymphadenectomy. We conclude that SN biopsy is a useful tool to individualize the operative
procedure, and laparoscopic local resection can be safely performed using SN guidance in selected patients with early gastric
cancer. 相似文献